A8L V8-4.2L (BFM) (2004)
Valve Guide: Testing and Inspection
Valve Guides, Checking
Special tools, testers and auxiliary items required
‹› Dial gauge holder (VW 387)
‹› Dial gauge
Test Sequence
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Insert the valve into the guide. The end of the valve stem must be flush with the guide. Due to the slight difference in stem dimensions, ensure that
only an intake valve is used in the intake guide and an exhaust valve in the exhaust guide.
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Determine tip clearance.
Wear limit
‹› If the wear limit is exceeded, re-measure using new valves. If the wear limit is still exceeded, replace the cylinder head. The valve guides cannot
be replaced.
‹› If the valve is to be replaced as part of a repair, use a new valve for the calculation.